Process for the manufacture of detergent compositions



5 2 9 9 LAruvum.

NOV. 3, 1970 GABLER ETAL 3,538,004

PROCESS FOR THE MANUFACTURE OF DETERGENT COMPOSITIONS Filed March 5,1967 United States Patent 667 Int. Cl. Clld 7/56, 3/075, 7/38 us. (:1.252-99 13 Claims ABSTRACT OF THE DISCLOSURE Production of detergentcompositions containing sodium tripolyphosphate with the aid of sodiumtripolyphosphate having a bulk density higher than 550 grams/liter andcontaining 20 to 100% phase-I, wherein pulverulent detergent componentsare mixed and the resulting mixture is sprayed thereafter with liquid orpasty detergent components, inside a turbulent air mixer.

The present invention relates to a process for the manufacture ofpulverulent detergent compositions, wherein the individual detergentcomponents are mixed and the resulting mixture is sprayed withwash-active substances, inside a turbulent air mixer.

It has already been proposed to produce detergents by sprayingwash-active substances on pulverulent skeleton material of a detergent,inside a turbulent air mixer. The various skeleton substances shouldeither be premixed in a mixer and introduced thereafter into theturbulent air mixer, or they should be conveyed continuously andseparately from reservoirs to the turbulent air mixer, inside whichwash-active substance and water are sprayed simultaneously on thepulverulent skeleton material which is thereby granulated.

Universally useful detergent compositions formulated in accordance withmost recent developments in detergent chemistry contain variouswash-active substances, for example, as set forth later herein andsilicates, carboxymethyl cellulose, optical brighteners, perfume, sodiumperborate, water and in addition thereto about 40-50% sodiumtripolyphosphate as their principal ingredient. Commercial sodiumtripolyphosphate is known to react with water applied thereto byspraying, while forming the hexahydrate, the reaction being accompaniedby considerable evolution of heat. However, the hexahydrate is formed soreluctantly, while the hydrous, wash-active substances are sprayed onthe pulverulent skeleton material, that the bulk of the heat evolved isset free only after removal of the spray product from the turbulent airmixer. The temperature of the spray product is then found to increaseand readily decomposable detergent components, for example perborates,are found to decompose under the action of the heat of hydration setfree subsequently. Furthermore, as a result of the sodiumtripolyphosphate undergoing hydration practically after removal of theproduct from the turbulent air mixer, the spray product produced in theturbulent air mixer is found to be moist and to have poor flowproperties provided that the said product contains the quantity ofwash-active substance necessary for a detergent composition. In order to3,538,004 Patented Nov. 3, 1970 ice obtain a useful and flowabledetergent, it is necessary to subject the product to prolonged ripening.

The conventional spray-mix processes, wherein a hydrous wash-activesubstance is nozzle-sprayed on pulverulent skeleton material ofdetergents containing sodium tripolyphosphate, have all been foundheretofore to entrain considerable difficulties which originate from thedissipation of the heat of hydration set free during that treatment.This is the reason why the suggested one-step production of completedetergent compositions based on sodium tripolyphosphate, moreparticularly of detergent compositions containing thermally readilydecomposable components as an additional ingredient, for exampleperborates, has failed to gain commercial interest, It has thereforebeen necessary to use multiple-step processes to that effect.

It has now unexpectedly been found that the difliculties mentioned abovecan be obviated when, inside a turbulent air mixer having an associatedspray device, a liquid or pasty detergent component is sprayed on sodiumtripolyphosphate with a content of phase-I-material of 20 to 100%,preferably 40 to by weight.

Sodium tripolyphosphate with a content of phase-I- material as set forthabove and with a bulk densit higher than 550 grams/liter, preferablyhigher than 600 grams and up to about 700 grams/liter, shouldadvantageously be used for the production of detergent compositionshaving a high bulk density.

The process of the present invention can be used more especially for themanufacture of detergent compositions which include at least onecomponent readily decomposable by thermal means, for example perborate.The liquid or pasty detergent components include primarily water and/ orwash-active substances.

As a result of its high hydration velocity, sodium tripolyphosphatecontaining phase-I-material is found to be more rapidly hydrated onbeing sprayed with water and wash-active substance, inside a turbulentair mixer. The heat set free is immediately dissipated by the cold airtravelling continuously through the turbulent air mixer, and the sprayproduct leaving the turbulent air mixer is found to be flowable and tohave a temperature which no longer produces decomposition of thethermally readily decomposable components.

Conveniently, the air flowing through the turbulent air mixer is socontrolled in temperature and/ or quantity that firstly the heat ofhydration is dissipated and that secondly the temperature necessary forthe hydration to occur fairly rapidly is maintained.

The liquid or pasty detergent components primarily include water and/orwash-active substances. These latter include, for example, the followinganionic representatives:

Alkylaryl sulfonates, real soaps (alkali metal salts of saturated andunsaturated fatty acids, such as oleic acid, palmitic acid, stearicacid, behenic acid, coconut oil fatty acid, tallow oil fatty acid, palmkernel oil fatty acid or other fatty acids produced from natural oilsand fats); salts of aminocarboxylic acids, salts of high or low-aeylatedamino-carboxylic acids; fatty acid sulfates; sulfates or phosphates offatty acid esters or amides; primary or secondary alkyl sulfates orsulfonates; sulfates, sulfonates or phosphates of esterified oretherified polyoxy compounds; and sulfates, sulfonates or phosphates ofsubstituted polyglycol ethers;

The following non-ionic representatives, for example:

Esters or ethers of polyalcohols and alkyl, acyl or alkylaryl polyglycolethers; and

The following cationic-active representatives, for ex ample:

Alkylamine salts; quaternary ammonium salts; alkyl pyridinium salts;ordinary and quaternary imidazoline salts; alkyl diamines andpolyamines.

A considerable advantage offered by the process of the present inventionresides in the fact that it admits of continuous operation, thepulverulent components being then simultaneously mixed and sprayed withthe liquid or pasty detergent components.

Turbulent air mixers having associated spray devices are useful forthis.

Needless to say that the pulverulent detergent components can first bepremixed and the resulting mixture sprayed with the liquid or pastycomponents. The premixing should conveniently be achieved using aconventional air mixer, which is placed after the turbulent air mixerand may be used for adding further pulverulent components to the sprayproduct produced inside the turbulent air mixer.

In accordance with a further feature of the present invention, theliquid or pasty detergent components can be sprayed through a pluralityof nozzle rings, more particularly through two nozzle rings arranged oneabove the other or through two adjacent nozzle rings, ingredientscontaining fatty acid components being sprayed, for example, separatelyfrom the alkaline components.

The accompanying drawing is a schematic representation of an exemplaryapparatus for carrying out the spraymix process inside a turbulent airmixer, the material to be sprayed travelling first through an air mixer.

The pulverulent detergent components are gently mixed in air mixer 1using air as the mixing agent. The mixing time comprises a period of 10to 20 seconds to ensure a uniform flow even of particularly finepulverulent material, without formation of bridges. The mixing isachieved batchwise, each batch being fed to secondary tank 2. The

mixed material accumulating in tank 2 is conveyed through a coarsedosing sluice 3 into a tiltable balance 4 having relatively smalldimensions and delivering the material to hopper 5.

Balance 4 is operatively associated with a timing relay which, after apredetermined period of time, places the balance in tilted position todeliver a char e into the hopper 5. During the same period of time, bematerial contained in the hopper 5 is fed through an infinitely variablebucket wheel sluice 6, a worm conveyor 7, and a flywheel 8 to apneumatic conveyor or lift 9. The conveyor 9 delivers the material intoa treatment chamber 11 through a separator 10 which discharges thematerial in the lower portion of the treatment chamber 11.

The interior of treatment chamber 11 is maintained under a negativepressure of 50-80 mm. water column. The conveying air for the pneumaticconveyor 9 fiows through blower 12, a return line 13 and the flywheel ina continuous cycle. By observation of an inspection glass 14, themetered quantities of material supplied by the bucket wheel sluice 6,having an infinitely variable drive, can be so regulated that hopper 5is empty when the next charge is delivered from the balance 4. Thismeans a very accurate control of the metered quantities of dry substancesupplied, because the balance determines the constancy of weight fromOne batch to the next. In other words, the balance can be adjusted todeliver, for example, 5 kg. of material at intervals of 14 seconds, andthe bucket wheel lock 6 can be adjusted to distribute the material,again within 14 seconds. Glass cylinder or inspection glass 15 permitthis to be controlled again. Any interruption or gap in the flow ofmaterial can be equalized by adjustment of the infinitely variabledrive. The flywheel 8 has the function of accelerating the material tothe conveying speed to avoid a pulsating conveying movement, and alsothe function of reducing the pressure downstream of the bucket wheellock, by means of an injector (not shown in the drawing).

These steps are also necessary to ensure undisturbed flow of powderedsubstances of different nature through the bucket wheel lock.

The negative pressure produced in the treatment chamber 11 by the lowpressure blower 12, and which can be varied by the regulating flaps 16and 16a, causes air to penetrate into the treatment chamber through anoutlet 17 and through the descending material. This results in thematerial being catapulted upwardly in a central fountain while forming acloud into which the spray nozzles 18, arranged as an annular set sprayfinely divided liquid through apertures 19.

This method of spraying prevents sprayed material from depositing on thejacket of the treatment chamber and enables a maximum surface contactand uniform distribution of the liquid in the dry material to beobtained.

The liquid is fed as usual by means of a dosing piston pump 29,including the necessary safety fittings, and is delivered through apressure-equalizing tank 28 to the main access diaphragm valves 24.Downstream of the diaphragm valve there is arranged a pressure filter 23which is directly in front of the associated annular nozzle ring. Theliquid from the pressure filter flows through the annular distributionconduit 22 to the individual nozzle connections 20, separately closableby a hand valve 21. An outlet conduit is disposed diametrically oppositethe inlet conduit, the outlet conduit being arched upwardly through 180of arc to a level which is below the level of the individual nozzleconnections from the annular conduit to the nozzle.

The conduit can be discharged through a diaphragm valve and through alateral offtake provided with a hand valve 26. Diaphragm valves 24 and25 are remotely controlled by a suitable control valve associated witheach one thereof. The hand valve 26 serves to regulate the amount ofliquid injected under the required nozzle pressure.

Preferably, the hand valve 26 is designed as a needle valve, and isarranged to be throttled until the desired working pressure has beenattained.

The liquid flows from hopper 27 to a suitable tank or is returned totank 30 which is normally charged from a liquid preparation plant (notshown in the drawing).

These tanks are equipped with level indicators, thermostats andautomatic controls. Discharge from the tanks is effected by a conduitextending to the suction sides of the dosing pump, the conduit having ahand valve 31 therein.

In order to maintain and adjust the separation to an optimum degree, andto effect eflicient return of the dust through blower 34 and separator33 to treatment chamber 11, a regulating device is arranged between thelatter and separators 33, in the suction line in front of the blower,the regulating device comprising a pivotal flap valve 16 and a slidevalve 161:. When the flap valve 16 is closed, the air current throughthe treatment chamber is throttled. The cross sectional area above theflap for the intake of fresh air increases. This cross sectional areacan be so regulated by means of an additional slide valve 16a that theseparators 33 perform an optimum degree of separation.

. The harmful effects of pulsation currents, occurring in the spray ortreatment chamber, on the separation eddies are avoided by exhausting,from both separators, some air along with the dust and injecting it bymeans of a separate high pressure blower 34 and connecting line 36tangentially into the spray chamber in the same direction as theconveying current. Each separator is exhausted by means of a separateexhaust line, and these two lines are united immediately ahead of blowerintake 34. Inside the suction bends there are provided several aperturesor openings 35 which are covered by rubber sleeves 37 and which areopened only when clogging is found to have occurred.

Exhaust of air from the separators is effected by a suction blower 32,and the exhaust air is delivered to a pressure filter 38 having acollecting hopper, an outlet duct 39, and a collecting bag 40.

The following examples illustrate the process of the present invention:

EXAMPLE 1 A mixture formed of 400 kg. sodium tripolyphosphate having abulk density of 620 grams/liter and containing 60% phase-I, 50 kg.sodium silicate, 40 kg. magnesium silicate, 40 kg. carboxymethylcellulose, 200 kg. sodium perborate and 2 kg. optical brightener wassupplied continuously to a turbulent air mixer and sprayed therein,within minutes, with (l) a spray mixture formed of 168 kg. alkylarylsulfonate (75% strength) and 46 kg. water and with (2) a spray mixtureformed of nonyl phenol polyglycolether and perfume, the spray mixturesissuing through separate nozzle-rings arranged in annular fashion. Acomplete, fiowable detergent powder with a bulk density of 490grams/liter was obtained. The sodium perborate could not be found tohave decomposed.

EXAMPLE 2 400 kg. sodium tripolyphosphate having a bulk density of 620grams/ liter and containing 60% phase-I were sprayed, inside a turbulentair mixer, with (1) a spray mixture formed of 168 kg. alkylarylsulfonate (75% strength) and 46 kg. water and with 2) a spray mixtureformed of 54 kg. nonylphenol glycolether and a slight proportion ofperfume, the spray mixtures issuing through separate nozzle-ringsarranged in annular fashion. 40 kg. sodium silicate, 50 kg. magnesiumsilicate, 40 kg. carboxymethyl cellulose, 200 kg. sodium perborate and 2kg. optical brightener were added, inside an air mixer, to the sprayedproduct so made. A flowable final product with a bulk density of 520grams/ liter was obtained. The sodium perborate could not be found tohave decomposed.

EXAMPLE 3 A mixture formed of 400 kg. sodium tripolyphosphate having abulk density of 630 grams/liter and containing 60% phase-I, 40 kg.magnesium silicate, 170 kg. sodium perborate and 2 kg. opticalbrightener was sprayed, inside a turbulent air mixer, with (l) a spraymixture formed of 166 kg. tallow oil fatty acid, 71 kg. coconut oilfatty acid and 30 kg. fatty alcohol polyglycolether, issuing through afirst set of nozzles arranged in annular fashion, and with (2) a spraymixture formed of 67 kg. sodium hydroxide solution (50% strength), 55kg. water and perfume, issuing through a second set of nozzles arrangedin annular fashion. A foaming detergent composition based on soap andhaving a bulk density of 430 grams/liter was obtained. The perborateremained undecomposed.

EXAMPLE 4 400 kg. sodium tripolyphosphate having a bulk density of630'grams/liter and containing phase-I was sprayed, inside a turbulentair mixer, with a spray mixture formed of 166 kg. tallow oil fatty acid,71 kg. coconut oil fatty acid, 30 kg. fatty alcohol polyglycolether,issuing through a first set of nozzles arranged in annular fashion, andwith a spray mixture formed of 67 kg. sodium hydroxide solution (50%strength), 55 kg. water and perfume, issuing through a second set ofnozzles arranged in annular fashion. 40 kg. magnesium silicate, 170 kg.sodium perborate and 2 kg. optical brightener were added thereafter,inside an air mixer, to the sprayed product so made. A flowable,strongly foaming detergent composition based on soap and having a bulkdensity of 460 grams/liter was obtained. The sodium perborate remainedundecomposed.

6 EXAMPLE 5 A mixture formed of 400 kg. sodium tripolyphosphate having abulk density of 630 grams/liter and containing 60% phase-I, 40 kg.sodium silicate, 40 kg. magnesium silicate, 40 kg. carboxymethylcellulose, 200 kg. sodium perborate, 2 kg. optical brightener and '90kg. soap powder was sprayed, inside a turbulent air mixer, with (l) aspray mixture formed of 80 kg. alkylaryl sulfonate strength), 68 kg.water and a slight proportion of perfume, and with (2) 40 kg. ofnonylphenol polyglycolether, the spray components issuing throughseparate nozzle-rings arranged in annular fashion. The detergentcomposition obtained as the final product had a bulk density of 480grams/liter; it was fiowable and foamed but slightly.

EXAMPLE 6 400 kg. sodium tripolyphosphate having a bulk density of 630grams/liter and containing 60% phase! was sprayed, inside a turbulentair mixer, with a spray mixture formed of kg. alkylaryl sulfonate (50%strength), 68 kg. water and a slight proportion of perfume, issuingthrough a first set of nozzles arranged in annular fashion, and with 40kg. nonylphenol polyglycolether issuing through a second set of nozzlesarranged in annular fashion. kg. soap powder, 440 kg. sodium silicate,40 kg. magnesium silicate, 40 kg. carboxymethyl cellulose, 200 kg.sodium perborate and 2 kg. optical brightener were added thereafter,inside an air mixer, to the sprayed product so made. A flo-wable,slightly-foaming detergent composition with a bulk density of 500grams/liter was obtained.

We claim:

1. A process for preparing pulverulent detergent compositions consistingessentially of (A) [dry pulverulent sodium tripolyphosphatecontaining20-100% by weight of Phase I material and having a bulkdensity greater than 550 grams/liter,

(B) an organic detergent or mixture thereof in liquid or pasty form, and

(C) detergent additives, in dry pulverulent form,

selected from the group consisting of silicates, optical brighteners,carboxymethyl cellulose, sodium perborate and mixtures thereof, saidprocess comprisingspraying the (B) component, in the presence ofwater,onto the (A) component, wherein the (C) components are-dry mixed withthe (A) component before, during or after the spraying step, and whereinthe spraying is conducted inside a turbulent air mixer.

2. The process of claim 1 wherein the sodium tripolyphosphate consistsessentially of 40 to 80% by weight phase-l material.

3. The process of claim 1, wherein the sodium tripolyphosphate has abulk density of 600 and up to about 700 grams/liter.

4. The process of claim 1, wherein the temperature inside the turbulentair mixer is regulated by varying the temperature and quantity of theair travelling through the turbulent air mixer.

5. The process of claim 1 wherein dry pulverulent (A) and (C) componentsare mixed and (B) components are sprayed thereonto simultaneously.

6. The process of claim 5, wherein the mixing and spraying steps areachieved inside a turbulent air mixer which is provided with nozzles.

7. The process of claim 1 wherein the (A) and (C) components arepremixed in a conventional air mixer.

8. The process of claim 1 wherein the (C) components are mixed, insidethe turbulent air mixer, with the product formed by spraying (B) on (A).

9. The process of claim 1, wherein the (B) components are sprayedthrough a plurality of nozzles arranged in an nular fashion.

10. The process of claim 9, wherein the (B) components are sprayedthrough two sets of nozzles arranged in annular fashion, one above theother.

11. The process of claim 9, wherein the (B) components are sprayedthrough two adjacent sets of nozzles arranged in annular fashion.

12. Process of claim 1 wherein different (B) components are sprayedseparately from each other.

13. The process of claim 1 wherein a slight proportion of perfume ismixed with the (B) components prior to the spraying step.

References Cited UNITED STATES PATENTS 2,308,992 1/1943 Mertens 252-97 8FOREIGN PATENTS 3/1936 Great Britain. 11/1935 Great Britain.

5 MAYER WEINBLATT, Primary Examiner D. L. ALBRECHT, Assistant ExaminerUS. Cl. X.-R.

